Tory MP Bob Neill's letter to the Metropolitan Police contains no evidence that the law may have been broken in seats other than Falkirk.

In an attempt to challenge Labour's assertion that the alleged abuses in Falkirk were a one-off, Conservative MP and party vice chairman Bob Neill has written to Metropolitan Police Commissioner Bernard Hogan-Howe asking him to investigate the selections in Ilford North and Lewisham Deptford.

In the case of the former, he writes: "In Ilford North, it has been reported that Unite were offering their members free Labour Party membership in exchange for attending a meeting with General Secretary Len McCluskey. Given that this constituency appears on a Unite target list along with Falkirk, I believe that the circumstances of this membership recruitment merit investigation."

He adds: "a London Labour activist Mandy Richards has alleged that Unite are ‘bankrolling’ a number of ‘orchestrated’ campaigns, and she singles out Lewisham Deptford for special attention. Again, given that this constituency appears on Unite’s secret list I am deeply concerned that Falkirk-style abuses may also have taken place."

In neither case is there any evidence that illegal activity has taken place. Offering members free Labour membership in return for meeting Len McCluskey is not against the law and nor is "bankrolling" or "orchestrating" campaigns.

Quite rightly, then, both Labour and Unite have responded by accusing the Tories of "wasting police time". A Labour spokesman said: "This is a silly political stunt. We have no evidence of possible criminal behaviour anywhere outside Falkirk. If Bob Neill has, he should produce it. If he has not, he should stop wasting police time."

A Unite spokesman said: "The Conservatives are wasting police time and trying to engage the police in a disgraceful political witch hunt. We strenuously reject any suggestion of criminality or that we have broken Labour party rules.

"Using the police to score political points and diverting their attentions away from making our communities safer is obscene.

"The Tories’ smear tactics are designed to scare ordinary people away from engaging in politics and ensure it becomes the preserve of an Eton educated elite."

CCHQ has responded by noting that Unite has not accused Ed Miliband of "wasting police time" in the case of Falkirk, asking whether this is "an acceptance of illegality". In that constituency, Unite is accused of signing up members to Labour without their knowledge or consent, an allegation that the Tories are notably unable to repeat in the case of Ilford North and Lewisham Deptford.